On the origin of magnetoresistance in ferromagnetic perovskite structures

In the presence of a nonuniform distribution of spin interactions in ferromagnetic perovskite materials, thermally activated magnetic domains appear. These domains are different from ordinary static ferromagnetic domains, rather their structures depend on temperature, magnetic field, and details of the distribution of magnetic interactions. Due to the half-metallic nature of these materials, magnetic domain boundaries contribute significantly to their electrical resistivity. Magnetoresistive effects are discussed within this framework.